1. Technical Field of the Present Invention
The present invention generally relates to methods and apparatuses that test memories for errors, and more specifically, to such methods and apparatuses that test embedded memories for errors.
2. Background of the Present Invention
The electronic industry is in a state of evolution spurred by the recent changes in technology which have allowed greater functionality in smaller devices. This has resulted in the explosion of new found uses for such small devices (e.g. medical, monitoring etc.), as well as greater functionality in increasingly smaller electronic devices.
The evolution has caused electronic devices to become an inseparable part of our society. Consumers are now buying and demanding electronic devices which are smaller, more powerful, and faster at unprecedented rates. These demands are constantly driving the electronic industry to exceed limitations which were previously considered unsurpassable.
One area ripe for improvement is the testing of embedded memory within Integrated Circuits (ICs). This is particularly true for Multi-port memories which are now being used in numerous applications such as microprocessors and communications devices. Previous methods used for testing embedded multi-port memories are often inapplicable as a result of the surrounding high gate count and the sheer number of ports. Specifically, the high gate count often makes complete tests of the multi-port memories impossible or extremely difficult because of the problems associated with reaching the data, address, and control signals from external pins. In addition, the sheer number of ports in a memory makes testing extremely difficult due to the number of possible simultaneous operations and paths in and out of the memory.
It would, therefore, be a distinct advantage to have a method and apparatus that would use portions of the embedded memories themselves to perform tests on their integrity. The present invention provides such a method and apparatus.